HMS NETWORKS CANbridge NT Lua ADK Bridge Router User Guide

CAN@net NT/CANbridge NT Lua ADK  

Descripon of Ixxat Lua ADK  

2. Descripon of Ixxat Lua ADK  

The Ixxat Lua ADK is based on the standard Lua 5.3.5 disribuon, a fully featured implemenaon of Lua 5.3. The  

implemenaon is opmized for embedded system development and execuon to provide a scripng framework  

that can be used to deliver useful applicaons within the limited RAM and Flash memory resources of embedded  

processors.  

• All standard Lua language constructs and data types are working.  

• Main Lua standard libraries core(partly), coroutine, string, math, debugand tableare  

implemented.  

• File handling uncons like require, dofile, and loadfileare missing. To be able to load other Lua  

les, like json.lua and misc.lua, the syslibrary provides the dofileuncon that is similar to the original  

uncons.  

2.1. Dierence between Standard Lua and Ixxat Lua ADK  

Lua is primarily an extension language that makes no assumpons about a main program. Lua works embedded  

in a host applicaon to provide a powerful, lightweight scripng language for use within applicaons. The host  

applicaon can invoke uncons to execute a piece of Lua code, can write and read Lua variables, and can  

register C uncons to be called by Lua code. Through the use of C uncons, Lua can be augmented to cope  

with a wide range of dieren domains, thus creang customized programming languages that share a synaccal  

framework.  

The Ixxat Lua ADK is a rmware extension and must be layered over the standard rmware. The hooks and  

features of Lua enable the Ixxat Lua ADK to be seamlessly integrated without losing any of the standard Lua  

language features. The rmware has replaced some standard Lua modules that do not align well with the  

rmware. For example, the standard ioand oslibraries do not work, but are partly replaced by the libraries  

can, mqtt, and sys. To write to the terminal window that is provided by the CAN-Gateway Conguraor the  

uncon print(string)is used by default.  

The main impacts of the Ixxat Lua ADK are how applicaon programmers must approach the developing and  

structuring of their applicaons. The ADK is nonpreempve and event driven. Tasks can be associated with given  

events by using the ADK API to registering callback uncons to the corresponding events. Events are queued  

internally within the ADK, and then the associated tasks are called one at a me. Each task returns the control to  

the ADK when run to compleon (nished successfully).  

The ADK libraries act as C wrappers around registered Lua callback uncons to enable these to be used as ADK  

tasks. Therefore an event-driven programming style must be used in wring Lua programs.  

2.2. Lua Library Funcons Enabling the Regisraon of Lua Callbacks  

The following library uncons dene or use callbacks:  

• sys.call_after()in Lua module sys  

• can.register_msg()in Lua module can  

• mqtt.subscribe()in Lua module mqtt  

For canthe standard Lua callback uncon on_canis used and for mqttthe standard Lua callback uncon  

on_mqtt.  

The libraries (can, sys, mqtt, etc.) use the ADK callback mechanism to bind Lua processing to individual events  

(for example a CAN message recepon). Developers should make full use of these events to keep Lua execuon  

sequences short.  

For more inormaon see the module documenaon in Lua API Funcon and Module Reference, p. 9.  

Page 2 of 20  

4.02.0332.20002 Version 1.5  

VIEW FULL SCREEN PDF MANUAL

General	Details
Name	HMS NETWORKS CANbridge NT Lua ADK Bridge Router User Guide
Make	HMS NETWORKS
Language	English
Filetype	PDF (Download)
File size	MB

Download PDF

(1 votes, average: 5.00 out of 5)

Loading...

• ALL WI-FI INSTRUCTIONS & USER MANUALS
• HMS NETWORKS

Questions and Answers (0)

If you have any questions regarding HMS NETWORKS CANbridge NT Lua ADK Bridge Router User Guide, please ask here and describe the problem in detail.